SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9a4e0e91e713d531925b34209d1142d34c5879f227fa22aab23e27bdb0d9a4d' 
  AND token = 'SRZ/Br1a1sA9qwgtaNHyaYbKz/3Ir1j0iJAar7ZOQpc=' 
  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"
    }
  }
}