SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab02123e3d8fa1f087d45f24015db2bb8a9a54a4cd6ed04457b951eff173235e' 
  AND token = 'eoeVmpK2JA5IcpXYd0SViTdzDBPS47dB4kBam6DCwfc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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