SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7da6e1a4f666a1afd7044fda2a5f1a1d54823d7267c5b1cf0385783ad7409db4' 
  AND token = 'qq/EcPQW/OVU4jPX6Ppgvt7TS/GpARm3jUFKUjUyBBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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