SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22eb2c4e0034c8e53a3070f2461a5190b35014fd91f9dc4733bd3623aca72d06' 
  AND token = 'dCoMFdpXcOfIUUUASmb6CdnBFMQ1hGlYFybQmuIflGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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