SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '053d1ae38355f3c53f043579a9a168277d31d8022b1ffe0c62a3b595ad3aee54' 
  AND token = '+njfeJrGfHffa2nBRvijJs6zJ2FNjKIsABU9t6VP+jw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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