SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '788c53bcfe48f6e4d342f5bf162ab4c6c69ef60870deaeb747c8248076c5b88b' 
  AND token = 'NCyUFdAomZsVSyFC5WNDn3Oij7v3bCa9RF/wdesOKx4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}