SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f22fa643cb972e608fc483e203463f1395ba4d475d55898307116ebb370adaef' 
  AND token = '6B6ISHfnHcl0VGPcreZy8BOGlviJ3y5unOk44Frt5fw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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