SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '523b21747fae761bc4f6e666de17270dcab0d0fd6ba7dde8d4a826234bdb3cc0' 
  AND token = '/9bRw40sA7F9bcZoodROVsQLamDKGLQ6aa4gUsXg3j0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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