SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b54cccf3226b203127f3b17abe4f63ff8201a401d1901a3ee2ee46555da872f0' 
  AND token = 'zazzYihp2DJnGjOcAP5EmQnxB9D2BV1Naz5dsYCLrKM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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