SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2d940b7363d46bae72ed369e684bff52e15e3465aa3923031b0e0cf8eeb5037' 
  AND token = 'q+CtBLUDVvEVsg4ZCmIAX6BOkql50O2cVTESRdYsLTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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