SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be64ae673e3349f9da6d6c928c18972221850971713992bbbb81d87d5e60cc25' 
  AND token = 'BECypTqIqwTVTejKmL2IF1+dAnipdQAqjmQUO/eFOR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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