SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4edb058dc4d0bea81fd69c4dd42387bbf256366bdede67af6d5a01806281bc4' 
  AND token = '32sSVcxfEncKn0b/QSrzN5XnPuXWDR2nmKMy7Du4daE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}