SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be72f86a843e85b0a3dc8af6b5bf0020309ac7a3b54c0fbb979dea2a61cdb2d5' 
  AND token = 'gF0Dm1CHDE8+3ZGJhnKAYl/pPsmdo/5FkIVt/VKPPtY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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