SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f44a5aac99898b2f9cf0fcb04eba44971ebc6b9ed2c8fc81938032eb88c3db41' 
  AND token = 'GGJs54XRsQ5ncR8ZKs4NLTupyv41MNBrpaRARNxwWFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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