SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d470c1ddcb4f796ae4bd34ba8e8eab7b4643b21100bbe3bc8cf01cdf31adc0e' 
  AND token = 'HRLwq/w3VrHexHZJPCgAzuINjZVA7Lo1FMyb1OHz1DM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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