SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb531d9f5f2c3de975cdc774d2a3e0df67d5bba68352719b2d4e15e09c3cb680' 
  AND token = '9GAavAEcaBaV0jbEC4EsXSyW2z0LWciynHXdimVQul0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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