SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37ccc64804f55d2c4017fb3917f023db794a4c6cb05f18e79ca8c80367354019' 
  AND token = 'egXD2QIGzg8vEBqIEAiCCbmu8J/MmR+zSCVoQQrrkao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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