SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3810da80ae05f2525b25675187335cddcc1f8d091bab503b0aa26582a1c7fae1' 
  AND token = 'dBvVqsnsLuEyJfuLmF2cw0rt0qFwsFicHA2VRHFxO2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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