SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'faf80d00490ca77be08e3bfc2d01e175600adef9ecd953b6a528716031ea9b9d' 
  AND token = 'NAdrgsItfiYKhBOL+BBmom3UXKCqICUQ8iCPE5hqbKk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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