SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8acbceb9ec785f6b72aa95f8d551f19695ec411e975d3bbcd69d24df03a192a' 
  AND token = 'oJTPVBJH3qZvmrC7pnwAS2XebBSjymSEqLtI/gehDNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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