SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f766b458c97bdce9ea7e73e6e86f260f0a1c07befd71239506aa185bd61fd09' 
  AND token = 'oEMiKeyhxuHGgUkDl0SNtyDpzCuZ/efOJvXWixc//20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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