SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61f4b710bae180ed94fb248155a514b8ec5ce5ee0187c0b6d5ecd1db55fb05e3' 
  AND token = 'BsKORjm75Yg831i2lIxurpPBCVPcfG71/njkyT2zuX0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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