SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce6826d14bcb95a83711acac0ebca74f0bc2fc1a394b0cdf118d069c7b2ed122' 
  AND token = 'gOSDP19AjMLvJXMRZ7F4zSGkNAR8hdFvqH67T3ICdLg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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