SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '248f3e18dc40830e634538e66efa724ef32c811b8e6a71ca2157825ac7cf3f17' 
  AND token = 'xuIv23qZr16kU07G3xqxB46pOGTdkqvhkIasqWi1CB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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