SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0665b47915341d3143b1664091849d3034f928ef4c6e466ffe141b215a315cd1' 
  AND token = 'iiRnbhWjiIiDUVTYJtSdMuSS7zSCOY4OMoC2CKwNDmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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