SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b657ee613f68169c93ec8fc3872f0c05a573521fba260904b711ec0c74ca2c0c' 
  AND token = 'hDPTKKPDDILDON5N4y4JpzRCNiuh02svFzXiR1ouZsc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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