SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b591f597e4d37d8333791b828eccbac7e2af6679dd1cd42fcaea1b907158b896' 
  AND token = 'Kd+MFreH8eEA+w2p/FhV0uHPelSjRoTKDGEcOriqoIY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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