SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f95294beb01cf10900fa966703adda0819b4823bfc3d5170c80d644c5c44ec82' 
  AND token = 'IaomA/DKt/V3r9NPVrHYkbDUOL6H8tirr4SMcghMntI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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