SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f99debf746d2b13f9b381480edf0825f146e431fcabf7959f8b9273b1243cb9' 
  AND token = 'gOR/C/g7D8DT25XNAnwPg0y4BafkvtF+H/RopaVoL4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}