SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5eb73824dbb63b7f9ae65d806ff2ed59be133b164e8e0e58a72c5f0496401e23' 
  AND token = 'FHzSA+JAjnaXXzQU72kGFNNLSS/jQuay3+eOO/b2Ag8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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