SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e89802dd503e720b01feab9e46935406e375388cabb9f49728a6b99f65d98e92' 
  AND token = 'VWeeH1NYprHb+R9zQmG1G1REyiV3ou0LBVumNoOuQ/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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