SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2553ea92a7b04e070b0d83fad6ba47465aaea7bcdb3daeb564e82d5426ac7ee9' 
  AND token = 'NXNIEDF6nt9PkMj0gDL8tErRpxcizlErLjsFWGeMLRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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