SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '622e189cb7a23a003ac6a89146856338ebb24839fe6fae2d0c41ac523b39851c' 
  AND token = 'YIvL2cg8EyNdccKI8CWS9ELXNhsDDHD576a90hOnsJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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