SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa32eb25255775fd61603af0906d5a4b848be2c4a02161f26d5ac8fde95c1fbf' 
  AND token = 'q9zigZcrGkrslnBY2XTLQetDH78+JDGVhwHOMIfgznQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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