SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5edcb8630890e8be6eb08aa530fd362e5d791f9e9cc5fe95caabed3bd03c8d7' 
  AND token = 'P75+znc63VwCthJ9F5e4VW3If5ZkR08dghIQkJX4BX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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