SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eafdc1e7abde08ffad68ef5ed292c08a115e5c3d858824648fbb93470de9bd11' 
  AND token = 'C0OTNVME5gyvYxRPasfM28BDr3N/fvxOSfcUPSY4wik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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