SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '813533d4d9c5e27032fb6b7e36bc3bb3d147cc067217998c8ebede11ecc883e8' 
  AND token = 'RBXC1J4EM/73AshF5FERp/6swAa7ej7xENgltquUlhs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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