SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c458aafc4f2812c3f842f23c5b868220eadaa1ceaf303346be3fd42166911f89' 
  AND token = 'aBsTULNu9GA+V+Crhhjh1kx4aRASvvhZw4xrr6yS1a8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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