SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58d133b7d87d2e9b6455b9041d5a47693f87994e3f164fbc2ba3efe5b8278953' 
  AND token = 'sKXXVzx2xurNONzgqohUWLNJjBDg+klgKt5oVybhQKk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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