SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6b7ce9a82b23dc3a89fe605d402b922882a7c900a188f2de2ee470702090bf61' 
  AND token = 'n2OzzilmIyOxqDDgR4eGk+TdUo3N0Rloy0Ke0ODUq4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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