SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04fcafe454e758c75894f4b632483997db21efaddb2e0d71eee5210a3f145e1a' 
  AND token = '5Sa76CVQAd6l6oQohbGNN4bSyZWMDI1Jn2eMeVQuNYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}