SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '93e4390d5af6407096556d03dad7bdfb3457854af66ff655332410ee505a7ac9' 
  AND token = 'ylz3bHzZbAre/dYWqqxeve2/Qzb3akY3M2fU8f/P9h4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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