SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c3fd61cf8cfd62f24fa3ffa6edbbf82257debe5a22ec1457da70d319e0f024e' 
  AND token = 'xRY6oXrGCX/BLtxQnuUPxP5LMexAJSKWIq1EU4hXfaE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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