SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8852ccff9f2a3765366c0e3601917c5d8348749156ad9737446ce0a060af766f' 
  AND token = 'N24yW9Gp8NOyt/hMhZHFH1MoVRXMRroc3x0DdJcg56I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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