SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffffc25f53df406c46b06968691f30aaa56ce2a952b461cca1cd8e3a8d7a5a13' 
  AND token = 'kZ+nBUV9JVSm5fKU7Gnu8QSCdbsY8HPjCVy2Fluz6Lg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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