SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86ad0441a66df7bfd55bc9cd8de0babf7ded3f5cec51621b32191fe3ad4a707c' 
  AND token = 'Tz9hV3/ECzvyk/l2UhHOGnxgryPKhno0UR+ftK85O5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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