SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12de9fe7c0e97c58c49f59e10bb4a17de7c889d480fbe7ab2935128d4f397064' 
  AND token = 'l0Nh+T1bjmHpv6V3RAQAO5VtiO+4y2kxpFJAdw1RX2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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