SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40b8fc7337c4a8a6a133e1a62182428927d8e355438d7d4f30baf15ba39a6687' 
  AND token = 'uNh/a3w8LJduhXnfTLqt6BsCLS9rK/ilvYL6PGAu7pc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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