SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c2e5a768e27ecc0c02a605977c22b13601ff555bcf3ac59ab3992f7ff46ab3d' 
  AND token = 'NLTwlsivvssqmArvK76WH+QBDFTeKZ6LDPz4Y3/WITc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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