SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ba54265f76939838fd029f78aafcd7d1753e77ee16d777ce2f5aeb51818f185' 
  AND token = 'bqjqfHS6xkh+QvfxdElU48EpzgeZLi/eBxkiDwmEsHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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